It is urgent to study the damage mechanism of corn kernels and find ways of reducing the rate of kernel breakage in mechanical threshing. This paper, by studying the mechanical curves and deformation characteristics of corn kernels with different moisture contents, points out the brittle mechanical characteristics of corn kernel damage fracture with low moisture content, and clarifies the the variation law of mechanical properties of kernels with moisture contents. The experimental data of fatigue load - fatigue life curves of corn kernels with different moisture contents were described by the power function equation. At the same time, the fatigue life and damage characteristics of kernel with different moisture content were analyzed, and the accuracy of the fitting equation was verified. Through mathematical statistical analysis, the normal distribution curve of fatigue life was fitted, and the variation law of normal distribution curve with moisture content and fatigue load was determined.